Eric Holder, Attorney General of the United States, informed Congress today that "After careful consideration, including review of a recommendation from me, the President of the United States has made the determination that Section 3 of the Defense of Marriage Act (“DOMA”), 1 U.S.C. § 7, as applied to same-sex couples who are legally married under state law, violates the equal protection component of the Fifth Amendment."

Holder's letter is worth reading in full. It contains a lengthy and substantive discussion of the law, focusing on equal protection theory and doctrine to support this conclusion:

After careful consideration, including a review of my recommendation, the President has concluded that given a number of factors, including a documented history of discrimination, classifications based on sexual orientation should be subject to a heightened standard of scrutiny. The President has also concluded that Section 3 of DOMA, as applied to legally married same-sex couples, fails to meet that standard and is therefore unconstitutional.

Nevertheless, the letter states that DOMA will continued to be enforced by the Executive branch.

Holder also issued a Statement which outlines the arguments and conclusions.

This is a reversal of earlier policy in which the DOJ appealed a district judge's opinion that DOMA was unconstitutional. And it is quite different from the DOJ defense of DOMA in which the Obama Administration argued "DOMA is rationally related to legitimate government interests and cannot fairly be described as "born of animosity toward the class of persons affected.""

Holder will now "instruct Department attorneys to advise courts in other pending DOMA litigation of the President's and my conclusions that a heightened standard should apply, that Section 3 is unconstitutional under that standard and that the Department will cease defense of Section 3."